Priceline announced a crappy outlook and crashed 15% on the news. Perhaps Shatner had a rope around his waist when they shoved him off the cliff in his last ad for them. The company followed him into the abyss.
But hasn't this been happening A LOT lately? Just recently - Zipcar, Sealed Air, Aeropostale to name just a few.
Serious punishment. And if it happens enough the indices will follow. It's just math.